more zfs docs

docs/zfs.md

@@ -13,3 +13,33 @@ sudo zfs set compression=zstd tank/myzstddataset
 sudo zfs set mountpoint=/data/mydataset tank/mydataset
 ```
 
+## Maintenance
+
+### Get Status
+
+```
+sudo zpool status
+```
+
+### Replace Disk
+
+```
+sudo zdb
+sudo zpool status -g # Show by GUID
+sudo zpool offline tank <GUID>
+sudo zpool status
+# Remove old disk, insert new disk
+sudo zdb
+sudo zpool replace tank <OLD GUID> /dev/disk/by-id/<NEW PATH>
+sudo zpool status
+```
+
+## Initial Setup
+
+```
+sudo zpool create tank raidz1 sda sdb sdc
+sudo zpool set ashift=12 tank
+sudo zpool set autoexpand=on tank
+sudo zpool set compression=on tank
+```
+